Aristocracy

Autocracy

Rule by a a single individual
An autocracy is a form of government where the political power is held by a single individual. Atuocracy doesn't emphasize the hereditary or elective characteristics of a monarch, instead he rises to power through non-elective means. The autocrat needs some kind of power structure to rule. Only a boss of a street gang or a barbarian chieftain can truly rule with only his personal charisma and his fighting skills. Most autocrats depended on their nobles, the military, the priesthood or others, who could turn against the ruler and depose or murder him.

Democracy

Rule by the people
Democracy is rule by the people through representatives elected by them. The methods by which this rule is exercised, and indeed the composition of "the people" are central to various definitions of democracy, but the general principle is that of majority rule.

Gerontocracy

Rule by the elders
A gerontocracy is a form of rule in which an entity is ruled by leaders who are significantly older than most of the adult population. Often the political structure is such that political power within the ruling class accumulates with age, so that the oldest hold the most power. Those holding the most power may not be in formal leadership positions, but often dominate those who do.

Magocracy

Rule by the mages
A magocracy is a form of government in which society is ruled by mages, typically using their powers to either subtly or blatantly influence the population, maintaining stability. Mages are often considered an upper class in the society.

Monarchy - Absolute

Rule by one individual who attains position because of hereditary lines
An absolute monarchy is a form of government where the ruler has the power to rule his or her land or country and its citizens freely, with no laws or legally-organized direct opposition in force. Although some religious authority may be able to discourage the monarch from some acts and the sovereign is expected to act according to custom, in a monarchy there is no constitution or body of law above what is decreed by the ruler. Monarchy puts total trust in well-bred and well-trained monarchs raised for the role from birth.

Monarchy - Barbarian

Rule by one individual who attains position because of hereditary lines
Barbarian monarchies are primitive states found among the Northerners. At the apex of a society of mostly free men stands the monarch (almost always a king), who has a few limited functions.

To serve as judge during the popular assemblies.

To serve as a military leader during wars.

The office is hereditary, but they need the consent of the people before assuming the throne. All the sons of the king have the right to claim the throne, which often leads to co-rulership (diarchy) where two brothers are elected kings at the same time. This evolves into the territories being considered the hereditary property of the kings, patrimonies, a system which fuels feudal wars, because the kings can claim ownership of lands beyond their de facto rule.

Monarchy - Elective

Rule by one individual who is elected in some form
An elective monarchy is a monarchy whose reigning king or queen is elected in some form. They rule for a lifetime, almost with equal power as in absolute monarchy. Usually elected monarchs tend to be more receptive to the will of the people though, or the instance that voted for them.

Ochlocracy

Rule by the mob
Ochlocracy is also often refered to as "Mob Rule". There is no formal authority whatsoever, not even a commonly-accepted view of anarchism, and so disputes are raised, contended and closed by brute force - might makes right, but only in a very local and temporary way, as another mob or another mood might just as easily sway a decision. It is common to see Ochlocracy form of rule among humanoid tribes.

Oligarchy

Rule by a powerful minority
Oligarchy is a form of government where most or all political power effectively rests with a small segment of society (typically the most powerful, whether by wealth, family, military strength, ruthlessness, or political influence).

Plutocracy

Rule by the wealthy
A plutocracy is a form of government where all the state's decisions are centralized in an affluent wealthy class of citizenry, and the degree of economic inequality is high while the level of social mobility is low.

Theocracy

Rule through religion
Theocracy is a form of government in which a religion plays the dominant role. It refers to a form of government in which the organs of the religious sphere replace or dominate the organs of the political sphere as clerical or spiritual representative(s) of god(s). A Theocracy can be ruled by a council, or by a single individual, even a monarch, as long as he is the Head of Church.

Tribalism

Rule by the tribe
Tribalism is a social system where the society is divided into small, roughly independent subgroups, called tribes or clans. Tribal societies lack any organizational level beyond that of the local tribe, with each tribe consisting only of a very small, local population. The internal social structure of a tribe can vary greatly from case to case, but, due to the small size of tribes, it is always a relatively simple structure. The leaders emerging are often turned to due to their competence, thus elders often advice matters where wisdom in decisive, while proven warriors become war-chiefs at times of war.